1. Field of the Invention
The present invention relates generally to irrigation, and more specifically to apparatus and methods of controlling and implementing irrigation.
2. Discussion of the Related Art
Typical irrigation control systems cooperate with water valves and pumps to control the flow of irrigation water through a variety of water dispensing devices, including sprinklers, rotors, drip-lines, and other water delivery devices. These control systems are used in a wide variety of irrigation applications, from residential and commercial landscapes to golf course and agricultural irrigation.
Many irrigation systems and electronics are powered by 50/60 Hz AC voltage signals. Some systems further modulate this power source to provide data communication, for example, by selectively clipping the positive half of a cycle of the AC voltage signal. Data and power sent in this manner are often over a two-wire transmission line and are often referred to as a two-wire interface. Irrigation devices variously located in the field couple to the two-wire interface and derive their operational power therefrom. Some irrigation devices can demodulate the data by monitoring the received power signal. These irrigation devices can control water flow through valves based on received signaling, for example, by actuating one or more solenoid control valves.